Red Hat Security Advisory: thunderbird security update
Affects Red Hat thunderbirdSource GCVE Database
Mentioned vulnerabilities
Not known to be exploited · CVSS 9.8 Critical · fixed in Red Hat package updates : patch Red Hat thunderbird as a priority.
Data as of 26 Oct 2026, 10:12 UTC
- EPSS
- 0.5% chance of exploitation in 30 days – higher than 43% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 140.4
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 14 Oct 2025
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.
What to do
AI-suggested
Red Hat has released an updated Thunderbird package (version 140.4.0-2.el8_2) for Red Hat Enterprise Linux 8.2 that addresses these vulnerabilities. Users should apply this official update to remediate the issues. For detailed update instructions, refer to the Red Hat article at https://access.redhat.com/articles/11258. No additional mitigations are specified or required beyond applying the update.
Description
Multiple security vulnerabilities affecting Mozilla Thunderbird have been addressed in a Red Hat security update. These include memory safety bugs, out-of-bounds read/write issues, use-after-free conditions, cross-process information leaks, and improper handling of object properties. The update fixes these issues in Thunderbird ESR 140.4 and Thunderbird 144. The vulnerabilities are rated with a high severity impact. Users of affected Red Hat Enterprise Linux 8.2 systems are advised to apply the update to remediate these issues.
References
- access.redhat.com/errata/RHSA-2025:19938 (opens in a new tab)
- access.redhat.com/security/updates/classification/ (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2403763 (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2403765 (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2403768 (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2403769 (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2403770 (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2403774 (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2403776 (opens in a new tab)
- security.access.redhat.com/data/csaf/v2/advisories/2025/rhsa-2025_19938.json (opens in a new tab)